The present invention relates to a lamp and more particularly to a lamp wherein substantially all light emitted from a light source is directed in a desired direction.
A conventional lamp for a bicycle or like vehicle includes a light source, a concave mirror, and a lens. The lens comprises a central portion and a peripheral portion which portions have different directivity to light. That is, the central portion directs or deflects light from the light source, while the peripheral portion directs or deflects light which is emitted from the light source and reflected by the concave mirror. Thus, of the light emitted from the light source, the light reaching the peripheral portion of the lens goes through the lens without undergoing directivity by the lens so that such light hardly contributes to the illumination by the lamp.